Portable aerial



June 1l, 1929. M. MATHIESEN PORTABLE AERIAL Filed Dec. 5, 1924 Patented June 11, 1929.

UNITED STATES PATENT OFFICE.

MARIUS MATHIESEN, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, T0

' WILLIAM J'. SANDBERG.

PORTABLE AERIAL.

Continuation of application Serial No. 754,123, led December 5, 1924. This application led February My invention relates to improvements in portable aerials for use in radio work and has special reference to improvements in collapsible portable loop aerials.

The object oit my invention is to provide a loop aerial which shall be readily collapsible into a relatively small compact compass for transportation, and which shall be capable of being readily and quickly extended for use.

The device of my invention comprises an extensible mast combined with arms hinged to the mast, and insulators secured to the ends o'l'" the mast and arms upon which the aerial wire is wound in loop vform. One pair ot the arms is hinged to a member which is mounted to slide on the mast in the collapsing and extending operations, and the arrangement is such that the final posiY` tioning of this pair of arms in extended relation serves to tension the loop wires and hold them in proper and orderly extended relation.

Further features of importance will become clear from the following description taken in conjunction with the accompanying drawings forming part of this specification and in which Figure 1, is a perspective view of the device as it appears extended for use;

Figure 2, is an elevational view showing the device in collapsed condition;

Figure 3, is an enlarged, fragmentary view illustrating the telescopic connction of the two parts of the mast or central member and the hinging of one pair of arms thereto; and

y Figure 4, is a fragmentary, vertical, sectional View on the line 4 4 of Figure In the form of my improved device, as illustrated in the drawings, 1 illustrates a base upon which the loop device proper is adapted to be rotatably mounted to be swung around on a vertical axis for the purpose et' obtaining the best results. The device proper comprises a central vert-ical mast 2 which consists in the form shown of a lower tubular part 3 and an upper part 4, the lower partof which is adapted to slide up and down in the tubular part 3. rllhese two parts of the mast are so related that they cannot rotate in relation to'each other, pret- ,erably by both being square in cross-section and the part 4 fitting within the tubular Serial No. 11,213.

part. The device proper is rotatably mounted on the base by means of a vertical bearing pin or stud 5 fixed to the base and upstanding therefrom, and the lower end ot the tubular part ot the mast being filled with a plug 6 and provided with a vertical opening substantially fitting the pin 5. The up per member 4 of the mast is slidable down into the tubular part 3 to shorten the mast, as best shown in Figure 2, when the device is collapsed.

As the space available for such devices is often more or less limited horizontally, while being ample vertically, a particular teature of improved collapsible loop is that I am enabled to make a loop which is elongated vertically and reduced horizontally while yet carrying an ample length ot wire. The construction which enables me to attain this improved form of loop includes the provision of two pairs of horizont-al arms 7-8 and 9-10, respectively, spread apart vertically of the mast.. The lower pair of arms, viz, 7 8, are hinged to the sides of the upper end of the tubular part 2 of the mast, as shown at 11. The armsare secured above the hinges so that they can swing down parallel with the part 3 ot` the mast when they are collapsed. The inner ends ot' these arms 7 and S are arranged to contact squarely with t-he sides of the tube 3, when in extended position, and they are thereby prevented from being swung above a horizontal position. The upper pair of arms 9-10 are hinged to a short tubular member 12 arranged to slide up and down on the upper part- 4 otl the mast, the extended position being such that the two arms 9 and V10 are arranged horizontally and parallel with the lower arms 7 and 8.

At the outer ends of the arms and at the upper and lower ends of the mast, I provide laterally extending insulators or wire supports 13, each comprising a iixcd crossmember 14 and a removable cap member 15. The members 13 may be provided with spaced apart shallow notches 16 for receiving the turns of the aerial wire 17, and then when the cap members 15 are secured in position the wires are tightly lamped in position on the ends of the several arms.

For holding the mast 2 in extended position, I provide a simple means of latching the two members 3 and 4 together. As

Amast and adapted to proiect through an- CII shown, this means consists of a spring pressed plug or pin 18 mounted in a pocket V19 in the lower end `of the upper part 4 of the opening 2O provided in one side near the upper end of the tubular part 3 of the mast. I provide a spring 21 in the pocket 19 to press .the piny 18 outwardly and taper the outer end of the pin to facilitate the latching and unlatching of the two parts of the mast. The pin4 is provided with' an enlarged base to prevent its escape through the hole 20. v

The sliding member 12 is adaptedto be similarly latched to the upper part 4 of the mast, being provided with an opening 22 to receive a spring pressed latch pin 23.

During the .process of `winding the several turns of the wire 17 on the arms, the mast is preferably fully extended, and I preferably secure the sliding support 12 ofthe arms 9 and 10 in a position higher than the fully extended position, and with the arms 9 and 10 extending in a slightly upwardly inclined relation, as indicated in dotted lines in Figure 1, soy that when the device is completed and the support 12 is pushed down to its fully extended position the several turns of the wire 17 will be tensioned by the spreading apart of the free ends of the arms 9 and 10 m the extending operation.

The free end portions 24 of the wire 17 are.

preferably secured to the lower cross arm 13 and can be connected in Yany suitable manner with the devices for which the aerial is designed to be used. I

It is to be noted that in collapsing the device the sliding member 12 can iirst'be unlatched and slid up the upper part 4 of the mast, thus relieving thetension of the loop wire, and the two arms 9 and 10 swinging in against the. mast, then the two partsV of the mast can be unlatched and the upper part 4 telescoped down into the lower part 3, and at the same time the two lower arms 7 and l8 can be swung down and in against the lower part 3 of the mast, thus bringing the several'parts into compact collapsed rela-V tion. Y 'As many inodiications of' my invention will readily suggest themselves to one skilled in the art, I do not limit or confine my invention to the specific constructions and arrangements of parts hereinshown and described. This application isa continuation of my copending application entitled Folding loop aerial, filed December 5, 1924, Serial Number 754,123.

I claim: y

1. A Vcollapsible loop aerial comprising a i mast adapted to be positioned vertically and comprising a pair' of telescopic members, a pair ofcross arms hinged on one of said members, an arm support member slidable along the other of said telescopic members, a pair of cross arms hinged to said slidable member and means for securing said' telesco'pic-l members and said arms in extended position.

2'. A collapsible loop aerial comprising a two part mast, one part being a tube and the other part a rigid' member telescopically mounted in the tube, a pair of laterally extensible arms hinged to the inner end of the tubular member, an arm support slidable on the rigid member, and a second pair of arms hinged to said slidable arm support.

n to which is swiveled a vertically extending tube, horizontally extended arms hinged Ato the upper end of said tube, a vertical extension slidable within said tube, a collar slidable along said vertical extension and cross arms hinged to'said collar.

4. A folding loop aerial comprising a base, a mast rextending' vertically therefrom, said mast comprising a pair of telescoping members, a pair of cross arms hinged on one ofsaid members, and a collar slidable along the remaining one of said members, a pair of cross arms hingedto said'collar, and means for latching said members andy arms in extended position, and insulators carried at the ends of said members and arms, suitable for retaining against shifting an antenna wire looped around the same.

5. In a collapsible loop aerial, a two part mast adapted to be extended, oppositely disposed arms hinged tov onepart of the mast, a member slidable along the other part of the mast, a pair of oppositely disposed arms hinged at their innenends to said member, cross arms at the ends of the' mast and the several arms, an aerial wire wound on the cross arms, the sliding member being adapted to extend and collapse the armsv hinged thereto, and latch means forA retaining the sliding member inl arm extending position.

6. In a collapsible'loop aerial, al frame having a mast comprising two telescopically movable parts, latch means for holding said' parts in their extended positions, arms for the frame adapted to be extended laterally, a member slidingly mounted on one of the mast parts to which'a pair,Y of arms are hingedly mounted, an aerial wire wound around the extremities of thearms and mast when frame is not fully extended, the sliding member carrying the arms hingedthereto beingomovable along the mast to act, in conjunction with the arms hinged thereto, as a toggle lever to extend the frame and tension the turns of aerial wire. n

In testimony whereof, I have hereunto set my hand, this 18th day of February, ,1925.-

Y MARIUS MATHIESEN."

o. A folding loop aerial comprising a base 

